Mold for intraocular lens

ABSTRACT

The invention is a mold and method for using the mold to make a multi-stage intraocular lens. The mold is provided with a gate in fluid communication with a lens portion and/or haptic portion of the mold core. In addition, a gasket is provided around the mold core. As molding material is introduced into the mold via the gate, a vacuum is drawn around and through the gasket to evacuate air trapped in the mold core and to help pull the material through the mold core.

CROSS-REFERENCE TO RELATED APPLICATIONS

None.

STATEMENT REGARDING FEDERALLY SPONSORED RESEARCH OR DEVELOPMENT

Not Applicable.

APPENDIX

Not Applicable.

BACKGROUND OF THE INVENTION

1. Field of the Invention

This invention relates generally to molds and, more particularly, to amold for a multi-stage intraocular lens.

2. Related Art

Multi-lens intraocular lenses have been disclosed in U.S. Pat. No.6,488,708 B1 issued Dec. 3, 2002 (“the '708 patent”). Prior to theinvention disclosed by the '708 patent, lenses were only single stagelenses with haptics going from the lens to muscle tissue. The '708patent discloses multi-stage lenses that are stacked, with hapticstraversing between each lens, connecting each lens together.

While conceptually an excellent idea, there remains a need in the art toimprove the manufacture of such intraocular lenses, such as providing amold and molding method for making such multi-stage lenses.

SUMMARY OF THE INVENTION

It is in view of the above problems that the present invention wasdeveloped. The invention is a mold and molding method for making amulti-stage intraocular lens. Specifically, the mold has a core withlens cavities, haptic cavities, and a gate in direct fluid communicationwith one or more of the cavities. In addition, the mold is provided witha gasket surrounding the core.

In use, molding material is flowed through the gate and into thecavities. As the silicone flows into the cavities, a vacuum is drawnaround the core and through the gasket. The vacuum evacuates air trappedin the mold core and helps pull the molding material through the moldcore.

Further features and advantages of the present invention, as well as thestructure and operation of various embodiments of the present invention,are described in detail below with reference to the accompanyingdrawings.

BRIEF DESCRIPTION OF THE DRAWINGS

The accompanying drawings, which are incorporated in and form a part ofthe specification, illustrate the embodiments of the present inventionand together with the description, serve to explain the principles ofthe invention. In the drawings:

FIG. 1 is a perspective view of a multi-stage lens produced by thepresent invention;

FIG. 2 is a perspective view of the mold, mold core, material gate, andgasket of the present invention;

FIGS. 3A and 3B are top views of the mold core, illustrating theplacement of the gate;

FIG. 4 is a side view of the mold core;

FIGS. 5A and 5B are perspective views of the mold core sections; and

FIGS. 6A and 6B are partial cross-sectional views of the mold coreillustrated in FIGS. 3A and 3B, respectively.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

Referring to the accompanying drawings in which like reference numbersindicate like elements, FIG. 1 illustrates a multi-stage intraocularlens, shown generally at 10, which is produced by the present invention.It is understood that lens 10 is shown with a pair of lenses, but thatmulti-stage lenses having more than two (2) lenses may be produced bythe method of the present invention. The multi-stage lens 10 is providedwith an anterior lens 12 and a posterior lens 14 that are connected by afirst haptic 16, second haptic 18 and third haptic 20. The multi-stagelens 10 is preferably made from silicone. The haptics 16, 18, 20 arebendable, allowing the lenses 12, 14 to be adjusted relative to eachother. The haptics 16, 18, 20 can connect the lenses 12, 14 at theirperiphery 22 or in their interior region 24.

Turning now to FIG. 2, a mold, shown generally at 26, has a mold core28, a material flow gate 30, and a gasket 32. The mold core 28 has apair of lens cavities 34, 36 that are in communication with each otherthrough haptic cavities 38, 40, 42. The gasket 32 surrounds the moldcore 28, including the lens cavities 34, 36 and the haptic cavities 38,40, 42. The material flow gate 30 is in communication with any one ofmore of the cavities in the mold core 28. Preferably, as illustrated inFIG. 3A, the material flow gate 30 is in communication with one moldcore cavity, such as one of the lens cavities 34, 36, and spaced apartfrom the haptic cavities 38, 40, 42. The material flow gate 30 can alsobe in communication with multiple mold core cavities, including thehaptic cavities 38, 40, 42. For example, as illustrated in FIG. 3B, thematerial flow gate 30 is in communication with one of the hapticcavities 38 as well as the lens cavity 36.

As illustrated in FIG. 4 and FIGS. 5A and 5B, the mold 26 can be formedby a pair of blocks 44, 46 that enclose a center block 48. FIG. 4illustrates a side view of the mold core 28 with the center block 48 inplace between the pair of blocks 44, 46. FIG. 5A illustrates the innerportion of the block 44 on one side of the mold 26, and FIG. 5Billustrates the inner portion of the block 46 on the opposite side ofthe mold 26 together with the center block 48. The center block ispreferably connected to a handle 50 that extends through the blocks 44,46. The handle 50 is equipped with offset pins 52 that guarantee theproper installation of the center block 48 into the mold 26, preventingthe accidental insertion in a backwards or upside down orientation.

These views of the mold 26 in FIGS. 4, 5A and 5B show a particularembodiment of the mold core 28 in which exterior sides of the lenscavities 34, 36 are formed as recesses 54, 56 in the respective pair ofblocks 44, 46. The interior sides of the lens cavities 34, 36 areenclosed by opposing sides 58, 60 of the center mold 48. Similarly theexterior sides of the haptic cavities 38, 40, 42 are formed by hapticrecesses 62, 64, 66 in the pair of blocks 44, 46 while their interiorsides are enclosed by the circumference 68 of the center mold. It willbe appreciated that each one of the haptic recesses 62, 64, 66 hascomplementary recessed portions 70, 70′ in the respective blocks 44, 46.Accordingly, the haptic recesses 62, 64, 66 in each one of the blocks44, 46 are formed from a pair of partial haptic recesses in the blocks44, 46 (i.e., complementary recessed portions 70, 70′). The interfacebetween the complementary recessed portions 70, 70′ should be identicalin number, position and shape to reduce the potential for flashingand/or discontinuities in the haptics 16, 18, 20 during the moldingprocess. The blocks 44, 46 fit together snugly at their complementaryfaces 72, 72′ through hardware elements 74 that pull the blocks 44, 46together. As particularly illustrated in FIG. 4, the material flow gate30 is formed by a groove 76 in one of the blocks 44.

FIGS. 6A and 6B illustrate partial cross-sectional views of the moldcore 28 according to FIGS. 3A and 3B, respectively. The shape of thehaptics 16, 18, 20 and connection to the lenses 12, 14 can be changedthrough the use of different mold shapes. For example, the hapticcavities 38, 40, 42 may be in communication with the periphery 78 of alens cavity 34 or an interior region 80 of a lens cavity 36. Similarly,the haptic cavities 38, 40, 42 could have an accordion cross-sectionalshape 82.

In operation, the pair of blocks 44, 46 are locked in place while theyenclose the center block 48. A molding material 84 is flowed throughgate 30 into any one or more of the one mold core cavities. Then, avacuum is applied to the mold core 28 through the gasket 42. The vacuumevacuates the air from the mold core cavities and assists the moldingmaterial 84 in flowing through all of the mold core cavities in the moldcore 28.

In the preferred embodiment, the molding material 84 is silicone andfirst flows from the gate 30 into one lens cavity 34 and then flows intothe other lens cavity 36 through the haptic cavities 38, 40, 42. It willbe appreciated that, in an alternative embodiment, a lens 86 (see FIG.6B) could be made out of a different material and placed in one or bothof the lens cavities 34, 36. The lens 86 would at least partially fillone or both of the lens cavities 34, 36, and the molding material couldflow around a portion of the lens 86. For example, the lens 86 couldhave attachment grooves or orifices where the molding material wouldlock into the lens 86. Such alternative lens materials could includepolymethylmethacrylate (PMMA), glass, and acrylics. Generally, themolding material can be any type of transparent, pliable material, likesilicone and hydrogel. Other possible materials includehydroxyethylmethacrylate (HEMA) and polydimethyl siloxanes.

In view of the foregoing, it will be seen that the several advantages ofthe invention are achieved and attained. The embodiments were chosen anddescribed in order to best explain the principles of the invention andits practical application to thereby enable others skilled in the art tobest utilize the invention in various embodiments and with variousmodifications as are suited to the particular use contemplated.

As various modifications could be made in the constructions and methodsherein described and illustrated without departing from the scope of theinvention, it is intended that all matter contained in the foregoingdescription or shown in the accompanying drawings shall be interpretedas illustrative rather than limiting. For example, a multi-stage lenshaving three stacked lenses separated by three haptics may also bemanufactured by the present invention. In such a case, the gate 30 canbe placed in direct fluid communication with one lens cavity 34. Then,material is flowed through gate 30 into the lens cavity 34. As thevacuum is applied through the gasket 32, material flows through each ofthe haptic cavities 38, 40, 42, and into the connected lens cavities.Thus, the breadth and scope of the present invention should not belimited by any of the above-described exemplary embodiments, but shouldbe defined only in accordance with the following claims appended heretoand their equivalents.

1. A mold core for a multi-stage intraocular lens, comprising: a plurality of lens cavities; a plurality of haptic cavities in communication with said lens cavities; a material flow gate in direct communication with at least one of said haptic cavities; and a vacuum-sealing gasket surrounding said lens cavities and said haptic cavities.
 2. The mold core according to claim 1, wherein said material flow gate is in direct communication with at least one of said lens cavities.
 3. The mold core according to claim 1, wherein said haptic cavities are in communication with a periphery of said lens cavities.
 4. The mold core according to claim 1, wherein said haptic cavities are in communication with an interior portion of said lens cavities.
 5. The mold core according to claim 1, wherein said haptic cavities have an accordion cross-sectional shape.
 6. The mold core according to claim 1, further comprising a handle having offset pins connected to said mold core.
 7. The mold core according to claim 1, further comprising a preformed lens disposed in at least one of said lens cavities.
 8. A mold core for a multi-stage intraocular lens, comprising: a first block having a face with a first lens recess and a plurality of partial haptic recesses extending between said first lens recess and said face; a second block having a second lens recess and a complementary face with a shape corresponding to said face of said first block and a plurality of complementary haptic recesses corresponding in number, position and shape to said partial haptic recesses of said first block, wherein said complementary haptic recesses extend between said second lens recess and said complementary face; a mold core between said first block and said second block, wherein said mold core encloses said first lens recess, said second lens recess and said haptic recesses to form a plurality of lens cavities and a plurality of haptic cavities extending between said plurality of lens cavities; a material flow gate in direct communication with at least one of said haptic cavities; and a vacuum-sealing gasket surrounding said first block and said second block.
 9. The mold core according to claim 8, wherein said material flow gate is further comprised of a groove in said face of said first block.
 10. The mold core according to claim 8, further comprising a handle having offset pins connected to said mold core.
 11. The mold core according to claim 8, further comprising a pre-formed lens disposed in at least one of said lens cavities.
 12. A mold core for a multi-stage intraocular lens, comprising: a plurality of lens cavities; a plurality of haptic cavities in communication with said lens cavities; a material flow gate in direct communication with at least one of said haptic cavities; and a vacuum-sealing gasket surrounding said lens cavities and said haptic cavities.
 13. The mold core according to claim 12, wherein said material flow gate is in direct communication with at least one of said lens cavities.
 14. The mold core according to claim 12, wherein said haptic cavities are in communication with a periphery of said lens cavities.
 15. The mold core according to claim 12, wherein said haptic cavities are in communication with an interior portion of said lens cavities.
 16. The mold core according to claim 12, wherein said haptic cavities have an accordion cross-sectional shape.
 17. The mold core according to claim 12, further comprising a handle having offset pins connected to said mold core.
 18. The mold core according to claim 12, further comprising a preformed lens disposed in at least one of said lens cavities.
 19. A mold core for a multi-stage intraocular lens, comprising: a plurality of lens cavities; a plurality of haptic cavities in communication with said lens cavities; a material flow gate in direct communication with at least one mold core cavity, wherein said mold cavity is selected from the group consisting of lens cavities and haptic cavities; and a handle having offset pins connected to said mold core.
 20. The mold core according to claim 19, further comprising a vacuum-sealing gasket surrounding said lens cavities and said haptic cavities.
 21. The mold core according to claim 19, wherein said material flow gate is in direct communication with at least one of said haptic cavities.
 22. The mold core according to claim 19, wherein said material flow gate is in direct communication with at least one of said lens cavities and at least one of said haptic cavities.
 23. The mold core according to claim 19, wherein said haptic cavities are in communication with a periphery of said lens cavities.
 24. The mold core according to claim 19, wherein said haptic cavities are in communication with an interior portion of said lens cavities.
 25. The mold core according to claim 19, wherein said haptic cavities have an accordion cross-sectional shape.
 26. The mold core according to claim 19, further comprising a preformed lens disposed in at least one of said lens cavities.
 27. A mold core for a multi-stage intraocular lens, comprising: a first block having a face with a first lens recess and a plurality of partial haptic recesses extending between said first lens recess and said face; a second block having a second lens recess and a complementary face with a shape corresponding to said face of said first block and a plurality of complementary haptic recesses corresponding in number, position and shape to said partial haptic recesses of said first block, wherein said complementary haptic recesses extend between said second lens recess and said complementary face; a mold core between said first block and said second block, wherein said mold core encloses said first lens recess, said second lens recess and said haptic recesses to form a plurality of lens cavities and a plurality of haptic cavities extending between said plurality of lens cavities; a material flow gate in direct communication with at least one cavity in said mold core; wherein said mold cavity is selected from the group consisting of said lens cavities and said haptic cavities; a vacuum-sealing gasket surrounding said first block and said second block; and a handle having offset pins connected to said mold core.
 28. The mold core according to claim 27, wherein said material flow gate is further comprised of a groove in said face of said first block.
 29. The mold core according to claim 27, further comprising a pre-formed lens disposed in at least one of said lens cavities. 